Latex emulsions may be produced using PIE in which resins are dissolved in a mixture of water, base and organic solvent(s) (e.g., methyl ethyl ketone (MEK), isopropyl alcohol (IPA) or both) to form a homogenous water-in-oil (W/O) dispersion (i.e., water droplets dispersed in continuous oil). Subsequently, water is added to convert the dispersion into a stable oil-in-water (O/W) latex. In embodiments, the solvents, distillates and liquids of a PIE process are collected and reused (solvent reuse or SR) in a subsequent PIE process.
Amorphous polyester latexes may be produced using SR PIE with methyl ethyl ketone (MEK) and isopropyl alcohol (IPA) as solvents. The organic solvents may be removed via vacuum distillation under mixing at elevated temperature. SR processes for amorphous polyester resins provide savings in raw materials cost and solvent disposal, leading to reduction in toner production cost. Particle size of amorphous resins in an SR PIE process using MEK and IPA correlates with the amount of IPA in the mixture. An SR PIE process for crystalline resins, if possible, would be desirable.